基于L-D流动法则模糊弹粘塑性的有限变形分析

为了进行岩土材料有限变形的动力分析，采用Green应变和第二类Kirchoff应力描述材料的几何非线性。将隶属度函数引入到屈服函数中，并采用L-D屈服准则，得到了基于L-D流动法则的模糊弹粘塑性本构模型。应用非线性有限元原理，得到了土样动三轴实验有限变形的数值结果，并与小变形的数值结果和土样的动三轴实验结果进行了对比。通过对比发现有限变形的结果更加接近动三轴的实验结果，且模糊弹粘塑性模型能很好地反映循环荷载作用下岩土的动力性质，是岩土动力分析的一种有效方法.

Fuzzy Elasto-Visco-Plasticity Analysis of Finite Deformation Based on the L-D Plastic Flow Rule

To dynamically analyze the finite deformation of rock and soil materials, the Green strain and the 2nd Kirchoff stress were used to describe their geometric nonlinearity. Through introduction of a membership function into the yield function, a fuzzy elasto-visco-plastic constitutive model based on the L-D plastic flow rule was built. According to the principle of nonlinear finite element, the numerical finite-deformation results corresponding to the dynamic triaxial soil tests were obtained, and compared with those traditional small-deformation results. The comparison shows that the finite-deformation results were closer to the dynamic triaxial tested results. Moreover, the fuzzy elasto-visco-plastic model well reflects the soil and rock dynamic properties under cyclic loading, and thus makes an effective way for soil and rock dynamic analysis, given its relatively simpler mathematical formulation and more convenience for finite element programming.